package com.study.common.sql;

import org.apache.ibatis.cache.CacheKey;
import org.apache.ibatis.executor.Executor;
import org.apache.ibatis.mapping.BoundSql;
import org.apache.ibatis.mapping.MappedStatement;
import org.apache.ibatis.mapping.ParameterMapping;
import org.apache.ibatis.plugin.*;
import org.apache.ibatis.reflection.MetaObject;
import org.apache.ibatis.session.Configuration;
import org.apache.ibatis.session.ResultHandler;
import org.apache.ibatis.session.RowBounds;
import org.apache.ibatis.type.TypeHandlerRegistry;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.util.CollectionUtils;

import java.text.DateFormat;
import java.util.Date;
import java.util.List;
import java.util.Locale;
import java.util.Properties;
import java.util.regex.Matcher;

/**
 * 描述:数据库操作性能拦截器,记录耗时
 *
 * @outhor Administrator
 * @create 2018-11-07 13:41
 */

//@Component
@Intercepts(value = {
 @Signature(type = Executor.class, method = "update", args = {MappedStatement.class,
  Object.class}),
 @Signature(type = Executor.class, method = "query", args = {MappedStatement.class, Object.class,
  RowBounds.class, ResultHandler.class, CacheKey.class, BoundSql.class}),
 @Signature(type = Executor.class, method = "query", args = {MappedStatement.class, Object.class,
  RowBounds.class, ResultHandler.class})})
public class SqlStatementInterceptor implements Interceptor {

  private static Logger logger = LoggerFactory.getLogger(SqlStatementInterceptor.class);

  private Properties properties;

  public Object intercept(Invocation invocation) throws Throwable {
    Object returnValue;
    long start = System.currentTimeMillis();
    returnValue = invocation.proceed();
    long end = System.currentTimeMillis();
    long time = end - start;
    try {
      final Object[] args = invocation.getArgs();
      //获取原始的ms
      MappedStatement ms = (MappedStatement) args[0];
      Object parameter = null;
      //获取参数，if语句成立，表示sql语句有参数，参数格式是map形式
      if (invocation.getArgs().length > 1) {
        parameter = invocation.getArgs()[1];
      }
//      logger.debug("查询参数: " + parameter);
      logger.debug("query param: " + parameter);
      String sqlId = ms.getId();// 获取到节点的id,即sql语句的id
      BoundSql boundSql = ms.getBoundSql(parameter);  // BoundSql就是封装myBatis最终产生的sql类
      Configuration configuration = ms.getConfiguration();  // 获取节点的配置
      String sql = getSql(configuration, boundSql, sqlId, time); // 获取到最终的sql语句
    } catch (Exception e) {
      logger.error("拦截sql处理出错" + e.getMessage());
    }
    return returnValue;
  }

  // 封装了一下sql语句，使得结果返回完整xml路径下的sql语句节点id + sql语句
  public static String getSql(Configuration configuration, BoundSql boundSql, String sqlId,
                              long time) {
    String sql = showSql(configuration, boundSql);
    StringBuilder str = new StringBuilder(100);
//    str.append(sqlId).append(":耗时【").append(time).append("】毫秒");
    str.append(sqlId).append(" spend: [").append(time).append("] millisecond");
    String begin = "======sql begin=====";
    String end = "------sql end------";
    logger.info(begin);
    logger.warn(str.toString() + "\n" + SQLFormatterUtil.getInstance().format(sql));
    logger.info(end);
    return str.toString();
  }


  /*<br>    *如果参数是String，则添加单引号， 如果是日期，则转换为时间格式器并加单引号； 对参数是null和不是null的情况作了处理<br>　　*/
  private static String getParameterValue(Object obj) {
    String value = null;
    if (obj instanceof String) {
      value = "'" + obj.toString() + "'";
    } else if (obj instanceof Date) {
      DateFormat formatter = DateFormat
       .getDateTimeInstance(DateFormat.DEFAULT, DateFormat.DEFAULT, Locale.CHINA);
      value = "'" + formatter.format(new Date()) + "'";
    } else {
      if (obj != null) {
        value = obj.toString();
      } else {
        value = "";
      }

    }
    return value;
  }

  // 进行？的替换
  public static String showSql(Configuration configuration, BoundSql boundSql) {
    Object parameterObject = boundSql.getParameterObject();  // 获取参数
    List<ParameterMapping> parameterMappings = boundSql
     .getParameterMappings();
    String sql = boundSql.getSql().replaceAll("[\\s]+", " ");  // sql语句中多个空格都用一个空格代替
    if (!CollectionUtils.isEmpty(parameterMappings) && parameterObject != null) {
      TypeHandlerRegistry typeHandlerRegistry = configuration
       .getTypeHandlerRegistry(); // 获取类型处理器注册器，类型处理器的功能是进行java类型和数据库类型的转换<br>　　　　　　　// 如果根据parameterObject.getClass(）可以找到对应的类型，则替换
      if (typeHandlerRegistry.hasTypeHandler(parameterObject.getClass())) {
        sql = sql.replaceFirst("\\?", Matcher.quoteReplacement(getParameterValue(parameterObject)));

      } else {
        MetaObject metaObject = configuration.newMetaObject(
         parameterObject);// MetaObject主要是封装了originalObject对象，提供了get和set的方法用于获取和设置originalObject的属性值,主要支持对JavaBean、Collection、Map三种类型对象的操作
        for (ParameterMapping parameterMapping : parameterMappings) {
          String propertyName = parameterMapping.getProperty();
          if (metaObject.hasGetter(propertyName)) {
            Object obj = metaObject.getValue(propertyName);
            sql = sql.replaceFirst("\\?", Matcher.quoteReplacement(getParameterValue(obj)));
          } else if (boundSql.hasAdditionalParameter(propertyName)) {
            Object obj = boundSql.getAdditionalParameter(propertyName);  // 该分支是动态sql
            sql = sql.replaceFirst("\\?", Matcher.quoteReplacement(getParameterValue(obj)));
          } else {
            sql = sql.replaceFirst("\\?", "缺失");
          }//打印出缺失，提醒该参数缺失并防止错位
        }
      }
    }
    return sql;
  }


  public Object plugin(Object arg0) {
    return Plugin.wrap(arg0, this);
  }


  public void setProperties(Properties arg0) {
    this.properties = arg0;
  }
}